Posts Tagged ‘author’

"Text" Books in a (higher) education environment.

Friday, May 18th, 2012

Text books (is this a misnomer, much like “papers” are in journals?) in a higher-educational chemistry environment, I feel, are at a cross-roads. What happens next?

Faced with the ever-increasing costs of course texts, the department where I teach introduced a book-bundle about five years ago. The bundle included all the recommended texts for an appreciable discount over individual purchase. In their first week at Uni, students were encouraged to acquire the bundle. As it happened, I met them for a tutorial shortly after this acquisition. The bundle weighed some 9 kg, and came shrink-wrapped into a strapless plastic sheath, posing a rather slippery and weighty challenge for the student to get back to their residency. A few months later, I asked the students how they were getting on reading their newly acquired texts. You must appreciate that it does take a few months for students to start getting “street-wise” about their uni experience. One savvy student recounted they had learnt that if one did not remove the plastic outer layer from the bundle, it would retain much of its resale value to the next generation of incoming students.

Now, I will not mention the publisher of this particular bundle, but its cost is in the region of £50 per text. And for some students, the 1500 or so pages of each volume remain largely unread. Rarely if ever do I see these texts brought into tutorials, and I expect the margins remain blank, un-annotated with any questions or notes (it affects the resale value if you do that). Which is a stark contrast to how the students nowadays annotate their lecture note hand-outs often (but not invariably) issued to them at the start of a lecture. I also observe that increasingly my tutorials are effectively annotated by the students attending (2-4 pages of notes can be taken during a 50 minute discussion. The unit can be declared as pages, since this is also done on paper).

Despite these trends, pedagogic usage of tablet devices such as Kindles and iPads remains relatively low. It is a chicken-and-egg situation. The aforementioned book bundle is not available for these devices, and if it were, then in the current business model, it would be DRM (digital-rights-management) protected to prevent resale, and would also probably retain (if not exceed) the cost of the printed version. Hardly attractive to a student. The lecture notes we distribute (as printed handouts) do indeed come as PDF versions which can be placed on a mobile tablet, but this advantage alone has not sufficed to promote rapid uptake of tablet here. Few materials are specifically optimised to take advantage of the unique features of a tablet, and so the printed lecture notes are considered acceptable. Perhaps this comes to the core of what such tablets are supposed to be. Are they devices for “content consumption”, or should we also expect them to be capable of “content creation”? Lecture (and tutorial) annotation is of course content creation (or perhaps augmentation). 

I might also take a look at the situation from the point of view of the textbook author. Unless you are a big name, you might expect to redeem about 10% royalties from one of the traditional publishers of academic texts. It might take you a year or so to write it, and you would expect to issue a further edition five years down the line if the book is successful. Two generations ago, every academic might be expected to write at least one book. I suspect that aspect has reduced nowadays; authors can hardly be encouraged to write if they think there is a prospect that the shrink-wrapping might not even be removed! If you are intending to write a text about, lets say stereochemistry, you also have to accept the 2D limitations of a printed book, or the inability to say animate a reaction path.

Where are these thoughts leading? Well, I do have to give an explicit example; Steve Jobs’ vision of the educational text-book, re-invented along the lines of what he famously introduced for music distribution. There, he recognised that the (presumed illegal) sharing of music via download sites that preceded the iTunes store was not a sustainable model. The $.99 download was conspicuously cheaper than the price of a physical music CD (excepting classical music, which did become absurdly cheap in this form), and a compromise on sharing stipulated only on devices owned by you rather than more widely amongst your friends. The same model was introduced for the iBook store. Here, the author of an eBook (I am no longer calling it a textbook) can if they wish retain 70% of whatever income it generates (it can also be free of course). The unit price was a fraction of the traditional paper-based book, low enough that the DRM-imposed inability to resell it was less of an issue.

What are the downsides of moving on from paper?

  1. Well, unlike a paper book which is instantly useable, the reader has to purchase a device. This device can cost more than the book bundle referred to above, although at its cheapest, the device is actually only about half the cost of the book bundle. And one might expect that device to last only 2-4 years before it becomes obsolete.
  2. It can be lost or damaged, although unlike a paper book, the online content can be readily restored at zero cost .
  3. If you purchase an eBook for one (proprietary) device, you cannot transfer it to another such device (say Kindle to iPad or vice versa), although if the content is free, that would not matter.
  4. Authors of such texts will have to retrain themselves to produce ebooks; it is not just a matter of using a standard word processor any more. I suspect writing/imaging/styling/scripting/widgeting (a verb for this collective process is needed; how about to flow?) an ebook takes a lot longer than word processing a text-book.
  5. You might have to consider the ongoing cost of using an ebook. By this I mean the data-plan that you might need in place to download components which are not actually part of the book (see below).

The upsides? Well, rather than my producing a list at this point, you might want to take a look at the first two examples below, both created by Bob Hanson, and think about how such inclusion in an ebook might enhance it:

  1. A device-sensitive page for display (try this out on an iPad or Android tablet; the Kindle might be more of a challenge).
  2. A page for building and minimising a molecular model
  3. This example is included, since it belongs to a chemistry text book, but actually would exist on a mobile device in functional form, if not actually a component of an ebook.

So an ebook becomes an environment where you can download a model from public databases, and annotate it with properties etc. Or you could use your ebook to build a model from scratch, then minimise its (molecular mechanics) energy, to say explore conformational analysis in the context of a chapter on the topic.

Well, at the start I posed the question what happens next? The two above examples give possible answers. An equally interesting question might then be who makes it happen? Will that be the evolutionary role of the traditional publishing houses? Will a new generation of skilful author capable of “flowing” an ebook emerge? Will students instead favour retaining their dependency on paper? Watch this space.

“Text” Books in a (higher) education environment.

Friday, May 18th, 2012

Text books (is this a misnomer, much like “papers” are in journals?) in a higher-educational chemistry environment, I feel, are at a cross-roads. What happens next?

Faced with the ever-increasing costs of course texts, the department where I teach introduced a book-bundle about five years ago. The bundle included all the recommended texts for an appreciable discount over individual purchase. In their first week at Uni, students were encouraged to acquire the bundle. As it happened, I met them for a tutorial shortly after this acquisition. The bundle weighed some 9 kg, and came shrink-wrapped into a strapless plastic sheath, posing a rather slippery and weighty challenge for the student to get back to their residency. A few months later, I asked the students how they were getting on reading their newly acquired texts. You must appreciate that it does take a few months for students to start getting “street-wise” about their uni experience. One savvy student recounted they had learnt that if one did not remove the plastic outer layer from the bundle, it would retain much of its resale value to the next generation of incoming students.

Now, I will not mention the publisher of this particular bundle, but its cost is in the region of £50 per text. And for some students, the 1500 or so pages of each volume remain largely unread. Rarely if ever do I see these texts brought into tutorials, and I expect the margins remain blank, un-annotated with any questions or notes (it affects the resale value if you do that). Which is a stark contrast to how the students nowadays annotate their lecture note hand-outs often (but not invariably) issued to them at the start of a lecture. I also observe that increasingly my tutorials are effectively annotated by the students attending (2-4 pages of notes can be taken during a 50 minute discussion. The unit can be declared as pages, since this is also done on paper).

Despite these trends, pedagogic usage of tablet devices such as Kindles and iPads remains relatively low. It is a chicken-and-egg situation. The aforementioned book bundle is not available for these devices, and if it were, then in the current business model, it would be DRM (digital-rights-management) protected to prevent resale, and would also probably retain (if not exceed) the cost of the printed version. Hardly attractive to a student. The lecture notes we distribute (as printed handouts) do indeed come as PDF versions which can be placed on a mobile tablet, but this advantage alone has not sufficed to promote rapid uptake of tablet here. Few materials are specifically optimised to take advantage of the unique features of a tablet, and so the printed lecture notes are considered acceptable. Perhaps this comes to the core of what such tablets are supposed to be. Are they devices for “content consumption”, or should we also expect them to be capable of “content creation”? Lecture (and tutorial) annotation is of course content creation (or perhaps augmentation). 

I might also take a look at the situation from the point of view of the textbook author. Unless you are a big name, you might expect to redeem about 10% royalties from one of the traditional publishers of academic texts. It might take you a year or so to write it, and you would expect to issue a further edition five years down the line if the book is successful. Two generations ago, every academic might be expected to write at least one book. I suspect that aspect has reduced nowadays; authors can hardly be encouraged to write if they think there is a prospect that the shrink-wrapping might not even be removed! If you are intending to write a text about, lets say stereochemistry, you also have to accept the 2D limitations of a printed book, or the inability to say animate a reaction path.

Where are these thoughts leading? Well, I do have to give an explicit example; Steve Jobs’ vision of the educational text-book, re-invented along the lines of what he famously introduced for music distribution. There, he recognised that the (presumed illegal) sharing of music via download sites that preceded the iTunes store was not a sustainable model. The $.99 download was conspicuously cheaper than the price of a physical music CD (excepting classical music, which did become absurdly cheap in this form), and a compromise on sharing stipulated only on devices owned by you rather than more widely amongst your friends. The same model was introduced for the iBook store. Here, the author of an eBook (I am no longer calling it a textbook) can if they wish retain 70% of whatever income it generates (it can also be free of course). The unit price was a fraction of the traditional paper-based book, low enough that the DRM-imposed inability to resell it was less of an issue.

What are the downsides of moving on from paper?

  1. Well, unlike a paper book which is instantly useable, the reader has to purchase a device. This device can cost more than the book bundle referred to above, although at its cheapest, the device is actually only about half the cost of the book bundle. And one might expect that device to last only 2-4 years before it becomes obsolete.
  2. It can be lost or damaged, although unlike a paper book, the online content can be readily restored at zero cost .
  3. If you purchase an eBook for one (proprietary) device, you cannot transfer it to another such device (say Kindle to iPad or vice versa), although if the content is free, that would not matter.
  4. Authors of such texts will have to retrain themselves to produce ebooks; it is not just a matter of using a standard word processor any more. I suspect writing/imaging/styling/scripting/widgeting (a verb for this collective process is needed; how about to flow?) an ebook takes a lot longer than word processing a text-book.
  5. You might have to consider the ongoing cost of using an ebook. By this I mean the data-plan that you might need in place to download components which are not actually part of the book (see below).

The upsides? Well, rather than my producing a list at this point, you might want to take a look at the first two examples below, both created by Bob Hanson, and think about how such inclusion in an ebook might enhance it:

  1. A device-sensitive page for display (try this out on an iPad or Android tablet; the Kindle might be more of a challenge).
  2. A page for building and minimising a molecular model
  3. This example is included, since it belongs to a chemistry text book, but actually would exist on a mobile device in functional form, if not actually a component of an ebook.

So an ebook becomes an environment where you can download a model from public databases, and annotate it with properties etc. Or you could use your ebook to build a model from scratch, then minimise its (molecular mechanics) energy, to say explore conformational analysis in the context of a chapter on the topic.

Well, at the start I posed the question what happens next? The two above examples give possible answers. An equally interesting question might then be who makes it happen? Will that be the evolutionary role of the traditional publishing houses? Will a new generation of skilful author capable of “flowing” an ebook emerge? Will students instead favour retaining their dependency on paper? Watch this space.

Reactions in supramolecular cavities – trapping a cyclobutadiene: ! or ?

Sunday, August 8th, 2010

Cavities promote reactions, and they can also trap the products of reactions. Such (supramolecular) chemistry is used to provide models for how enzymes work, but it also allows un-natural reactions to be undertaken. A famous example is the preparation of P4 (see blog post here), an otherwise highly reactive species which, when trapped in the cavity is now sufficiently protected from the ravages of oxygen for its X-ray structure to be determined. A colleague recently alerted me to a just-published article by Legrand, van der Lee and Barboiu (DOI: 10.1126/science.1188002) who report the use of cavities to trap and stabilize the notoriously (self)reactive 1,3-dimethylcyclobutadiene (3/4 in the scheme below). Again sequestration by the host allowed an x-ray determination of  the captured species!

Scheme for production of 1,3-dimethylcyclobutadiene 3 and CO2.

The colleague tells me he has himself already penned an article on the topic and submitted this to a conventional journal. However, their rules decree that whilst it is being refereed, I could not discuss the article here, or indeed even name its author. Assuming his article is published, I will indeed reveal his identity, so that he gets the credit he deserves! Meanwhile, I will concentrate in this blog purely on two other aspects of this reaction which caught my own eye after he brought the article to my attention.

The reaction involves imobilising a precursor 1 in a crystalline calixarene network as shown above, and then in situ photolysis to form the Dewar lactone 2. Further photolysis then results in extrusion of carbon dioxide and the formation of 1,3-dimethyl cyclobutadiene 3 and CO2, both still trapped in the host crystals. Thus imobilised, here they both apparently remain (at 175K) for long enough for their X-ray structure to be determined. What attracted me to this chemistry was the potential of this reaction as a nice example of a Diels Alder reaction occuring in a cavity. The first example of such catalysis was reported by Endo, Koike, Sawaki, Hayashida, Masuda, and Aoyama (DOI: 10.1021/ja964198s) and I have used this in my lectures for many years. This latter example however illustrates the promotion of a cycloaddition, which inside a cavity is accelerated by a factor of ~105, rather than of the reverse cycloelimination. I explain this to students by invoking entropy. Normally, when two molecules react together, there is an entropic penalty, which can add 8 or more kcal/mol to the free energy of activation of a bimolecular reaction in the absence of the cavity.

Structure of entrapped 1,3-dimethylcyclobutadiene, obtained from the CIF file provided via DOI: 10.1126/science.1188002

By a strange coincidence, my name is also on a recently published article (DOI: 10.1021/ol9024259) with other colleagues on the use of (Lewis) acid catalysts to accelerate a type of reaction known as the Prins. This involves the addition of an alkene to a carbonyl group. Now as it happens, the reaction in the scheme above showing 42 happens to combine these features; it is both a Diels-Alder cycloaddition and also involves an alkene adding to a carbonyl compound! It is therefore noteworthy that the claimed reaction 123 + CO2 is done in the presence of a strong acid catalyst, the guanidinium cation 5, which is itself part of the structure of the calixarene-based host. It is represented as X in the scheme above, and can also be identified in the above 3D model via the light blue atoms.

There are however crucial differences between these two earlier examples I quoted and the reaction of 23; the latter is in fact a cycloelimination and not a (cyclo)addition. In other words, according to literature precedent, the guanidinium cation-based cavity should act to accelerate the reverse cycloaddition 42 rather than the forward cycloelimination. Since the isomerisation 34 is thought to be fast, the question arises: how rapid is the reverse reaction 42? In particular, is it slow enough to allow X-ray diffraction data to be collected for 3/4 over the necessary period of 24 hours or more? Legrand, van der Lee and Barboiu do not address this point in their article. Nor is there discussion there of how the cavity and the acid catalyst might influence the position of the equilbrium 23 + CO2.

This is where calculations can help. At the B3LYP/6-311G(d,p) level four different models were selected.

  1. Model A is a simple gas phase calculation for the singlet state, which reveals the free energy barrier for 42 is already quite modest for a Diels-Alder reaction (more typical values are ~22 kcal/mol), due no doubt to the instability/reactivity of the cyclobutadiene. However, at 175K, that would still be quite sufficient to prevent the reverse reaction from occurring to any extent over the period of X-ray data collection.
  2. Model B adds a condensed phase (water) to the model. This serves in part to simulate the condensed crystal environment (which is pretty ionic being a tetra ion-pair). The barrier drops to 12.1 kcal/mol.
  3. Adding one guanidinium cation to both these models (C and D) which simulate the Prins conditions, drops the barrier to 8.3 kcal/mol (model 4).
  4. You can inspect details of any of the calculations by clicking on the digital repository entry (shown as dr in the table), where full data is available.

None of these models includes the entropic effects of full constraint in a cavity (which I estimated above as capable of reducing the free energy barrier for reaction by ~8 or more kcal/mol). If this correction is applied to model D, it would reduce the barrier to ~0 kcal/mol! The calculations also reveal that the reverse reaction 42 is exothermic, and this exothermicity is enhanced by the acid catalyst 5. It would be further enhanced by reducing the entropy of reaction by pre-organizing the reactants in the cavity. The tendency must therefore be for 3/4 to revert to 2 on purely thermodyamic grounds, and only the presence of a significant kinetic barrier would allow them to exist as separate species. This barrier, as one might infer from the calculations shown in the table below, may not be a large one. Even a barrier of 8 kcal/mol might require cooling to significantly lower than 175K to render the reaction slow on a ~24 hour timescale.

Model ΔG4 → 2
kcal/mol
ΔGreac 4 → 2 Singlet-triplet
separation
A. Gas phase,X=none dr ts 16.8 dr -3.5dr +5.7 dr
B. Continuum solvent (water),X=none dr ts 12.1dr -6.0 dr +7.7 dr
C. Gas phase,X=guanidinium+ dr ts 6.1 dr -19.5dr +2.1dr
D. Continuum solvent (water),X=guanidinium+ dr ts 8.3 dr -10.1 dr +7.7 dr

So I end my own speculations here on the nature of the reaction reported by Legrand, van der Lee and Barboiu by asking: are the products they claim (1,3-dimethylcyclobutadiene and carbon dioxide) capable of existing as separate species for long enough inside their cavity, even at 175K, to allow for the collection of X-ray data for a structure determination?

I tend to think probably not (? rather than !). But do decide for yourselves.


Archived as http://www.webcitation.org/5rpkn2Z5S on 08/08/2010. See also this post.